In a letter sent last week, the Landmarks Preservation Commission affirmed its mid-July determination that the building, which Canadian developer Stephane Bolvin bought from Horovitz in April for $5.5 million, did not rise to the level of landmark status based on its architectural merits.

Duane argued that the house, where he attended political meetings on LGBT issues as a teenager, was valuable to the gay community.

"This building was a home for the first wave of gay activists in New York," he said. "There would be no Senator Tom Duane without this building."

The president of the Jim Owles Liberal Democratic Club, which is named in honor of a gay activist who lived in the house, said LGBT youth need to see the landmarks of their predecessors.

"It is vital that younger people have these kind of monuments to learn about our history and struggle for civil rights and liberation," Allen Roskoff said.

Bolvin, whose lawyer did not immediately return a request for comment, is planning a seven-story mixed-use development that will have two floors of retail, three single-floor apartments and a duplex penthouse, according to the website of his company, Nordica SoHo.

When Bolvin bought 186 Spring St., he told The Real Deal that he planned to use the building for "personal use" and not combine it with the project next door.

GVSHP executive director Andrew Berman said Bolvin would still profit from preserving the building and renting it out.

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